Taz 4 resurrection

I resurrected my Taz 4 from the shed recently and cleaned it up.

Before putting it away in a box, I began to do some upgrades to it, just Z probes and dual extruder.

As I remember about 4 years ago, I needed to flash the firmware and something went wrong I think.
So recently I embarked on trying to flash the firmware again, this time using the latest from Marlin, ver 2.1.2.2. With VS Code, PlatformIO, Auto Build Marlin and configs found at github: GitHub - MarlinFirmware/Configurations at release-2.1.2.2 I was able to build and upload successfully.

Everything seemed to work with above, but from the printers controls I am unable to home the machine or move the x,y,z axis. It shows on the display flashing ? for x,y,z. The only thing I can do is preheat the hot end and bed. Any ideas why I’m unable to home the machine or move any of the axis?

This machine is essentially stock aside from the firmware update. Dual extruder replaced with original extruder. The z-probe which is a Klicky PCB probe I’ve not yet installed. I used to have other z-probe sensors and I still have a BL Touch, but nothing is currently wired on the machine.

With this new Marlin software I’m unable to tell what is going on. Should I download some software or enable debugging and how can I debug this?

? for xyz is what it displays until it homes, that’s normal.

I’m assuming you’re using these as a starting point?
Configurations/config/examples/LulzBot/TAZ4 at release-2.1.2.2 · MarlinFirmware/Configurations · GitHub

I have no idea if that configuration has been maintained at all.

The part that stands out to me is the endstop switch configuration. The linked config has

#define X_MIN_ENDSTOP_INVERTING true  // Set to true to invert the logic of the endstop.
#define Y_MIN_ENDSTOP_INVERTING true  // Set to true to invert the logic of the endstop.
#define Z_MIN_ENDSTOP_INVERTING true  // Set to true to invert the logic of the endstop.

While lulzbot’s configuration for the Taz 6 (which used the endstops the same, AFAIK), is

// Mechanical endstop with COM to ground and NC to Signal uses "false" here (most common setup).
#if ANY(MiniV2, TAZPro, TAZProXT, Sidekick_289, Sidekick_747)
#define X_MIN_ENDSTOP_INVERTING true // Set to true to invert the logic of the endstop.
#else**
#define X_MIN_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.**
#endif**
#if ANY(Sidekick_289, Sidekick_747)
#define Y_MIN_ENDSTOP_INVERTING true // Set to true to invert the logic of the endstop.
#else
#define Y_MIN_ENDSTOP_INVERTING false // Set to true to invert the logic of the endstop.
#endif

It’s not miniv2, tazpro, xt, or a sidekick, so when compiling, it’s going to do this code:
#define X_MIN_ENDSTOP_INVERTING false
and
#define Y_MIN_ENDSTOP_INVERTING false

So the build you’re using is seeing the endstops as activated before they’re touched and not moving.

You can test really quick by holding down the endstop switches when you attempt to home. If things move, it’s that simple. Swap the inverting to false instead of true on x/y (and set your Z for whatever probing method you’re using).

However… Since this part of the configuration is wrong, I can’t imagine what else is wrong. Check that configuration!

Thank you for your reply. Still finding this to be an issue even when applying those changes.

Not unexpected, the configuration file probably hasn’t been touched in a long time, so there’s probably going to be a lot to discover and fix.

You’d probably be best served by pulling up the latest configuration files for a Taz 5 that Lulzbot has put out, and working that side-by-side with the latest bugfix build of marlin to build your starting point. Once that’s working, activate the BLTouch or whatever way you want to advance your firmware.

Hi Wrathernaut,

Thank you for your responses. Very helpful.
I’ve been able to build, upload and see the newer version of the software 2.1.2.2, I’m still unable to use the machine. I also found at your direction the configuration.h file for the Taz 5 and went line by line through the entire config.

I also grabbed the original Taz 4 and Taz 5 firmware from Lulzbot located here:
Index of /TAZ, I fixed a bug that was complaining about the fpos_t and simply renamed all instances to fpost instead. That fixed the issues and was able to upload and see version 2.0.0.1 with both instances.

However, I’m still having issues homing and see a red light on the board.
Maybe I messed up something when I tried to use the BLTouch a long time ago and wired something wrong. This time I’m going back to the original setup though with no probing.

I was hoping you might have, know where I can find, or know the wiring for the board itself.
I currently have the X and Y end-stops connected to min-x and min-y on the board, Z is connected to max-z. Not sure if that is correct or not. No other changes would have been made to the connections I believe.

Again thank you for all your help!

Z should be on the Min Z.

image